In Black & Veatch’s seventh-annual U.S. Electric Utility Industry Report, 376 utility executives listed aging infrastructure as a top five concern in 2013. As well they should.
In its “2013 Report Card for America’s Infrastructure,” ASCE reported that as of 2010, 70% of transmission lines and power transformers were at least 25 years old. Similarly, as of 2010, 60% of circuit breakers were more than 30 years old.
In a study prepared for the Edison Foundation, the Brattle Group predicts that we will have invested US$879.3 billion in power-delivery infrastructure between 2010 and 2030. The study, “Statistics from Transforming America’s Power Industry,” shows $581.5 billion going into distribution, $113.4 billion into bulk transmission (230 kV and up) and $184.4 billion
going to lower-voltage transmission.
In Aging Power Delivery Infrastructures (second edition), Lee Willis, senior vice president with Quanta Technologies, and Randall Schrieber, vice president at ABB, share perspectives gained from working closely with electric utilities.
The authors recommend that utilities prioritize based on both condition and on a criticality index, and that equipment in extremely poor condition always be taken out of service. Equipment rated as critical to the operation of the network is given priority when making investment decisions. The authors worked closely with utilities to develop detailed numerical prioritization schemes taking into account the cost of actions as well as the cost of consequences (good and bad).
Richard Brown, vice president with WorleyParsons, warns that looking at the average age of equipment can be misleading, especially in a service territory with significant load growth. Brown recommends that a utility focus on the “very old” equipment, which is typically located in the older parts of the system.
Dr. Don Russell, regents’ professor in the department of electrical engineering at Texas A&M University, also works closely with utilities and summarizes thusly: “Utilities certainly know how to replace old equipment with new and most would love to do so. However, money is the primary issue. Regulators have hesitated in our economy and political environment to approve large-scale renovation and replacement projects. Since we know what to do, if we only had money, the next question is, “What do we do if we don’t have lots of money?”
Russell recommends we manage aging infrastructure through true conditioned-based maintenance. Russell’s approach applies advanced waveform analytics and real-time monitoring to track the health of distribution systems that can identify ailing devices before an outage occurs.
John Miksad, senior vice president of electric operations at Consolidated Edison, informed me that his company has moved entirely from age-based to performance-based asset models. Also, after Con Edison suffered from superstorms Irene and Sandy, his company now considers more frequent severe weather as the new normal. Thus, Con Edison is addressing aging infrastructure and storm-hardening simultaneously as it changes out to submersible components and as it builds in operating flexibility with automated switches and additional supervisory control.
Doug Mader, former chairman of the AEIC Electric Power Apparatus Committee, also informed me that his utility has moved from an aged-based to a condition-based asset management model in addressing transmission assets. His utility looks at probability of failure as well as the cost of maintenance and repair. It also developed refurbishment programs that take into account the risk of a failure affecting the customer.
I talked to Jeff Fleeman, director of Advanced Transmission Studies & Technologies with American Electric Power’s transmission business, who wrote an article for T&D World (February 2013) on his company’s new Asset Health Center. Fleeman’s organization has a department dedicated to asset performance and renewal. This department evaluates T-line and T&D substation assets based upon age, condition, maintenance cost and criticality to prioritize asset renewal investments. The department is also working with ABB to build an automated analysis and decision-support platform that incorporates historical inspection and diagnostic data from multiple sources as well as real-time data from SCADA and health monitors. This will speed and simplify the data organization and analysis effort, and lead to reduced failures, optimized maintenance and, in a more automated fashion, prioritized replacement needs. The application tools will have numerous analytical and visualization functions, including a “maintain versus replace” decision model that will advise at what point in an asset’s life that replacement, rather than maintenance, should occur.
In summary, I am happy to report that our more progressive utilities are actively tackling aging infrastructure. These utilities realize it is not economically feasible to simply replace devices when they reach design life. Instead, utilities are making data-based decisions to replace or refurbish based on the criticality and condition of aging circuits.